Air-compressor.



W. N. DBNNISON. AIR COMPRESSOR. APPLICATION FILED FEB. 12, 1907.

1,023,820. Patented Apr.23, 1912.

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' eccentrically arranged the piston-wheel 4,

UNITED STATES PATENT OFFICE.

WILBURN N. DENNISON, OF MRGHANTVILLE, NEW JERSEY, ASSIGNOB TO VICTOR TALKING- MACHINE COMPANY, A CORPORATION OF NEW JERSEY.

AIR-COMPRESSOR.

i Specification of Letters Patent.

Patented Apr. 23, 1912.

To all whom it may concern.

Beit known that I, WILBURN N. -DENNI- son, a" citizen of the United States, and a resident of the borough of Merchantville, State of New Jersey, have invented certain new and useful Improvements in Air-Compressors, of which the following is a full, clear, and complete disclosure.

My invention relates to improvements in rotary air compressors and more particularly to that class wherein radial sliding piston-blades are carried by a' rotating piston-wheel set eccentrically within a cylinder.

The main object of my invention is to produce a machine which will be practically noiseless in its'operation, and which will give a-steady flow of air from its outlet.

Another object is to increase the efiiciency and reduce the noise of a machine of this type by providing an improved means for preventing leakage between the intake and compression sides of the cylinder.

Further objects of my invention are to simplify the construction of the machine, reduce the friction between its moving parts, and to make its wearing parts removable.

Other objects of my invention will be apparent as the device is further explained.

y invention consists in the novel construction, combination and arrangement of parts hereinafter described, and more par ticularly set forth in the claims and illustrated in the accompanying drawings, in which Figure l is an end elevation with a part broken away; Fig. 2 a longitudinal vertical section of the device; and Fig. 3 a detail in perspective, showing one of the pistonblades.

Referring to the drawings, the device comprises a'cylinder 1, provided at one end with a removable cylinder head 2, secured by bolts in the usual manner, and at its 0pposite end with a longitudinal eccentrically arranged reduced hollow extension 3, integral therewith. Within the cylinder is rigidly mounted upon the end of the shaft- 5, which is journaled in the bearings 66,

carried by they said extension 3 of the cylinder. The said piston wheel 4 is cylindrical in shape, and is provided with an inwardly extending hub of less diameter than the outer diameter of the wheel and the said extension 3 of the cylinder is divided by the bearings into two chambers, one of which is between thebearings, and the other of which is between the inner bearing and the main portion of the cylinder,'and communicates therewith, forming a recess concentric with the bearings for the reception of the said hub of the piston wheel. The hub of the wheel is provided with a central bore and the end of the shaft 5 is rigidly secured in said bore by-means of a pin or other suitable connection. The said bearings 6 are provided with spiral oil grooves 7, which are fed fromthe ollcups 8, located beneath "threaded into'the upper part of the cylinder.

The said inlet duct is provided with a reduced outer end, having an inlet orifice 14, less in area than the transverse sectional area of the duct, and having a diameter about, one fourth the diameter of the duct,

the purpose of which will be explained here-' inafter. Opposite the said outlet ports 11 is a vertically extending outlet chamber 15, opening into a vertical thimble 16, screw threaded into the upper part of the cylinder,

the said thimble being provided with a converging end 17 forming a socket for the attachment of a connection through which air is conveyed to any desired point.

The. iston-wheel 4 is provided with radial slots wlthin which are slidably mounted the piston-blades 18. These have a width equal to the distance between the opposite ends of the cylinder, and a length slightly in excess of the length of the radius of the said piston -wheel and the inner ends of the blades are notched as at- 19 to a depth slightly exceeding half the width of'the blade, and are arranged in said wheel so that the notched ends of the blades overlap during the operation of the compressor. The

outer ends of the blades are slightly rounded to avoid cutting the interior surface of the v bushing, and the inner ends of the blades are perforated at and by the current of air through the inlet chamber and inlet ports into the cylinder. The said cylinder bushing 9 is provided with an internal eccentric recess 22, the center of curvature of which is the axis of the piston-wheel, and its radius of curvature the radius of the piston-wheel, so that a bearing for said wheel is formed in said recess. Experience-has shown that this feature of the compressor is important in preventing leakage past the upper side of the piston-wheel, between the intake and compression sides of the cylinder, and also in reducing the noise which always occurs whenever there is a leak between the high and low pressure sides.

In the operation of this device the pistonwheel is driven at a comparatively high speed, creating through the action of the piston-blades, the outer edges of which are held in engagement with the inner'surface of the cylinder by centrifugal force only, a partial vacuum in the inlet chamber and inlet duct, the inlet orifice bein reduced as heretofore stated, and pur ose y too small to permit of the passage 0 sufiicient air to maintain the normal air pressure within these spaces. It has been found that the reduction'of the size of the inlet orifice lessens the noise of the operation of the compressor, and that a compressor constructed and operated as thus described is practically noiseless and delivers a steady flow of air from its outlet.

Having thus fully described my invention what I claim and desire to protect by Letters Patent, is

1. An air compressor having inlet and outlet ports, an elongated inlet duct having an inlet orifice with a diameter approximately equal to one quarter that of a transverse section of the duct.

2. An air compressor having inlet and outlet ports, an inlet chamber and an inlet duct opening into said chamber, said inlet duct having a reduced inlet orifice adapted to retard the inflow of air into said chamber, whereby a partial vacuum is formed in said chamber and duct.

3. An air compressor having an inlet duct provided with a reduced outer end and an opening for air in said outer end substantially smaller in area than the cross sectional area of said duct.

4. An air compressor having an inlet duct provided with a reduced outer end and an opening for air in said outer end substantially smaller in area than the cross sectional area of said duct, the opening inthe end being less than half the area of the duct.

5. An air compressor having an inlet duct, provided with an inlet orifice substantially smaller in area than the cross sectional area of said duct.

6. An air compressor comprising a casing having a restricted inlet and a relatively large outlet, and separate chambers respectively connected with said inlet and outlet, an annular bushing having foraminous regions local to said chambers, and a rotary eccentric piston mounted in said bushing and having reciprocatory blades centrifugally engaged with said bushing.

7 An air compressor having an inlet duct, and means to check the flow of air into said duct.

8. In an air compressor, the combination with a casing, of a cylindricahpiston having a reduced cylindrical inner end provided with a central bore, a driving shaft for said piston fitting within said bore and secured to said reduced end, the main portion of said piston being provided with diametrical slots extending from the outer end of said piston to the said reduced portion thereof, and radial piston blades mounted in said slots.

9. An air compressor havin inlet and outlet ports, and an elongate inlet duct having an inlet orifice of a cross section ap proximately one-sixteenth that of the cross section of the duct, the restricted inlet orifice being operative to greatly decrease the fluid pressure within said duct before entering the adjacent ports.

10. An air compressor having a multiplicity of inlet and a multiplicity of outlet ports, and an elongated inlet duct having a greatly restricted inlet orifice, the restricted inlet orifice being operative to greatly decrease the fluid pressure within said duct before enteringthe adjacent ports.

11. An air compressor having a multi plicity of inlet and a multiplicity of outlet ports, and an elongated inlet duct having an inlet orifice of less cross section than one half the cross section of said duct.

12. An air compressor havinga compression chamber, an inlet duct, and means adjacent said duct operative to greatly decrease the fiow of fluid into said duct before entering said chamber.

In witness whereof, I have hereunto set my7hand this 30th day of January, A. D. 190

WILBURN N. DENNISON. 

